Comparison Of Phyto-Chemical Properties, Anti-Oxidant And Anti-Diabetic Activity Of Hydro-Ethanolic Extracts Obtained From Six Seaweed Species By In-Vitro Enzyme Inhibition Methods

Abstract

The present study was conducted to compare the phytochemical properties of six different seaweeds like green algae (Caulorpa racemosa & Ulva faciata), red algae (Amphiroa fragilissima & Porphira indica) and brown algae (Sargassum cristaefolium & Turbinaria ornata) by using standard methods. The study revealed that, almost all six sea weeds (TO, AF, CV, SC, UF & PI) had flavonoids, poly phenols, carbohydrates, tannins, sterols, proteins & free amino acids. The alkaloids were present only in TO, AF, CV & PI and glycosides were present only in TO & UF. The anti-oxidant activity of HEEOSA was studied by in-vitro DPPH and nitric oxide scavenging assay methods. The anti-diabetic potential of HEEOSA was studied by using in-vitro enzyme inhibitory assays. The HEEOSA (TO, AF, CV, SC, UF & PI) showed significant dose dependent inhibitory effects on α-amylase with IC₅₀ values of 14.25 µg/ml, 9.14µg/ml, 15.53 µg/ml, 18.4 µg/ml, 11.24 µg/ml & 13.05 µg/ml respectively and the reference standard acarbose was found to be3.12 µg/ml. The HEEOSA (TO, AF, CV, SC, UF and PI) and the standard drug voglibose showed significant dose dependent inhibitory effects against α-glucosidase withIC₅₀values of 82.36 µg/ml, 65.34 µg/ml, 95.42 µg/ml, 100.89 µg/ml, 71.146 µg/ml, 73.94 µg/ml & 25.95 µg/ml respectively. The inhibitory concentration (IC₅₀) of HEEOS against standard ascorbic acid by DPPH scavenging assay was found to be 4.78, 4.17, 4.86, 4.67, 4.79, 4.85 & 3.91µg/ml respectively. Similarly, inhibitory concentration (IC₅₀) of HEEOS and ascorbic acid against nitric oxide scavenging assay was found to be 4.69, 3.35, 4.85, 5.18, 4.47, 4.22 and 1.92 µg/ml for TO, AF, CV, SC, UF & PI respectively. Among the above six species of marine algae, Amphiroa fragilissima had maximum potential as anti-diabetic agent with IC₅₀ value of 9.14 µg/ml and 65.34 µg/ml against α-amylase and α-glucosidase respectively, and also revealed its anti-oxidant potential with IC₅₀ value of 3.36 µg/ml against 1.94 µg/ml for standard ascorbic acid by NOSA method and IC₅₀ value of 4.17 µg/ml against the standard ascorbic acid (3.91µg/ml) by DPPH scavenging assay. Therefore, Amphiroa fragilissima could be selected for further studies like toxicity as per OECD guidelines and in-vivo studies by using animal models.